“It is like leaven, which a woman took and hid in three measures of meal, till the whole was leavened.”
Luke 13:21 — Greek Interlinear
Church Fathers on Luke 13:21
While His adversaries were ashamed, and the people rejoiced, at the glorious things that were done by Christ, He proceeds to explain the progress of the Gospel under certain similitudes, as it follows, Then said he, to what is the kingdom of God like? It is like a grain of mustard seed, &c.
In another place, a grain of mustard seed is introduced where it is compared to faith. If then the mustard seed is the kingdom of God, and faith is as the grain of mustard seed; faith is truly the kingdom of heaven, which is within us. A grain of mustard seed is indeed a mean and trifling thing, but as soon as it is crushed, it pours forth its power. And faith at first seems simple, but when it is buffeted by adversity, pours forth the grace of its virtue. The martyrs are…
Or else; The kingdom of God is the Gospel, through which we gain the power of reigning with Christ. As then the mustard seed is surpassed in size by the seeds of other herbs, yet so increases as to become the shelter of many birds; so also the life-giving doctrine was at first in the possession only of few? but afterwards spread itself abroad.